(Reading 7º, 8º) Pollution Facts & Types of Pollution
Pollution is the process of making land, water, air or other parts of the
environment dirty and unsafe or unsuitable to use. This can be done through the
introduction of a contaminant into a natural environment, but the contaminant
doesn't need to be tangible.
Land pollution
Land can become polluted by household garbage and by industrial waste. In
2010, Americans produced about 250 million tons (226.8 million kilograms) of
garbage, consisting of product packaging, grass clippings, furniture, clothing,
bottles, food scraps, newspapers, appliances, paint and batteries.
Commercial or industrial waste is a significant portion of solid waste. Hazardous
waste is any liquid, solid or sludge waste that contain properties that are
dangerous of potentially harmful to human health or the environment. Industries
generate hazardous waste from mining, petroleum refining, and pesticide
manufacturing and other chemical production. Households generate hazardous
waste as well, including paints and solvents, motor oil, fluorescent lights, aerosol
cans, and ammunition.
Water pollution
Water pollution happens when chemicals or dangerous foreign substances are
introduced to water, including chemicals, sewage, pesticides and fertilizers from
agricultural runoff, or metals like lead or mercury. According to the United
Nations, 783 million people do not have access to clean water and around 2.5
billion do not have access to adequate sanitation. Adequate sanitation helps to
keep sewage and other contaminants from entering the water supply. According
to National Oceanic and Atmospheric Administration (NOAA), 80 percent of the
pollution in marine environments comes from the land through sources such as
runoff. Water pollution can severely affect marine life.
Warming water can also be harmful. The artificial warming of water is called
thermal pollution. It can happen when a factory or power plant that is using water
to cool its operations ends up discharging hot water. This makes the water hold
less oxygen, which can kill fish and wildlife. The sudden change of temperature
in the body of water can also kill fish.
Air pollution
The air we breathe has a very exact chemical composition; 99 percent of it is
made up of nitrogen, oxygen, water vapor and inert gases. Air pollution occurs
when things that aren’t normally there are added to the air. A common type of air
pollution happens when people release particles into the air from burning fuels.
This pollution looks like soot, containing millions of tiny particles, floating in the
air. Another common type of air pollution is dangerous gases, such as sulfur
dioxide, carbon monoxide, nitrogen oxides and chemical vapors. These can take
part in further chemical reactions once they are in the atmosphere, creating acid
rain and smog. Other sources of air pollution can come from within buildings,
such as secondhand smoke.
Finally, air pollution can take the form of greenhouse gases, such as carbon
dioxide or sulfur dioxide, which are warming the planet through the greenhouse
effect. According to the EPA, the greenhouse effect is when gases absorb the
infrared radiation that is released from the Earth, preventing the heat from
escaping. This is a natural process that keeps our atmosphere warm. If too many
gasses are introduced into the atmosphere, though, more heat is trapped and this
can make the planet artificially warm, according to Columbia University.
Air pollution kills more than 2 million people each year, according to a study
published in the journal Environmental Research Letters. The effects of air
pollution on human health can vary widely depending on the pollutant.
Noise pollution
Noise pollution happens when the sound coming from planes, industry or other
sources reaches harmful levels. Research has shown direct links between noise
and health, including stress-related illnesses, high blood pressure, and speech
interference and hearing loss.
Light pollution
Some consequences of light pollution are:
Some birds sing at unnatural hours in the presence of artificial light.
Scientists have determined that long artificial days can affect migration
schedules, as they allow for longer feeding times.
Light pollution, called sky glow, also makes it difficult for astronomers, both
professional and amateur, to properly see the stars.
Plant's flowering and developmental patterns can be entirely disrupted by artificial
light.